ISO stands for International Organization for Standardization which isn’t terribly helpful in letting us know what it means. ISO was used to describe film “speeds” in the days of film. Films were graded by how “fast” they could expose for light. If you wanted a different ISO or speed film, you had to finish a roll and put in a new roll of film with a different ISO number.
Today in Digital photography as with most things, ISO is much easier, you (or the camera) can change it on the fly depending on conditions.
The best way to think of ISO is as the sensitivity of your camera’s sensor to light. The lower the number, the less sensitive to light your sensor is, the higher, the more sensitive.
So on a sunny day, you would want a very low ISO (most DSLRs bottom out at 100), while in a dark room, you might want a higher ISO.
How high an ISO is too high? As with most things, it depends. At very high ISOs, the camera introduces noise into the picture visible as extra dark pixels on your shot. This varies based on the camera sensor’s capability. Lower end camera’s may start to encounter noise at relatively low ISOs like 600-800, while higher end cameras may show little to no noise at much higher ISOs up to 12,500 and above.
Experimentation is the key.
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I get this question quite a bit, so I thought I would write a post to answer this FAQ. A couple disclaimers right from the start. I shoot Nikon cameras, that means I’m going to talk about Nikon DSLRs. Canon, Pentax, Sony and others make some fantastic cameras, I just don’t use them, so I can’t give you advice on those. Second disclaimer, I’m still an amateur/enthusiast photographer, I’ve learned a lot in the last couple years, most of it self-taught, but I’m not a professional.
Now on to the details. The Nikon DSLR universe is broken up into roughly 4 categories (by me): amateur, advanced amateur, enthusiast and professional. The amateur lines are the 3xxx series and the 5xxx series. the advanced amateur is the 7xxx series, the enthusiast is the 6xx, 7xx series and 8xx series and the professional is the Dxx series. Confused yet? Stick with me.
Amateur: The current models in this category are the D3300 and the D5500. They are Dx cameras which means they have a smaller digital sensor than Nikon’s larger DSLR. They can auto-focus on any compatible lens that has its own focusing motor (the cameras don’t have an internal focusing motor). This can limit which lenses can be used to full effect on the camera. These are great camera’s to start out in DSLR, especially if you aren’t sure how much you will use them. You will pay roughly $500 for the D3300 and roughly $750 for the D5500. My first DSLR was the D3100, the predecessor to the D3300. With these cameras you can take some amazing pictures.
Advanced Amateur: The D7200 is the current model in this category. With this category, you have the same sized sensor (Dx or APS-C also called a “cropped” sensor) as the amateur cameras, but you get two memory card slots, an internal drive focus-motor which dramatically increases the number of lenses your camera can fully use. There is also a big increase in the low-light capability of these cameras over the amateur ones. The D7200 is roughly $1100.
Enthusiast: The D610, D750 and the D810 are the current models in this category. These have an Fx or Full-frame sensor. This is a larger sensor than in the amateur and advanced amateur. All three have great low-light capability. The D610 and D750 have a 24 megapixel sensor and the D810 has a 36 megapixel sensor. The D610 retails for $1500, the D750 retails for roughly $1900 and the D810 for $2800. Of these three, I bought the D750 as it has the best low-light capability and has virtually all the capability of the more expensive D810. It does have a smaller sensor at 24 vice 36Mp but that isn’t terribly important unless you are cropping photos and then viewing/printing them at very large sizes.
Professional: The D4s is roughly $6000. For this dramatic increase in price you get a very well-built camera with incredibly detailed photos, great low-light capability and double the frames per second of other DSLRs. These cameras are built like tanks with metal bodies designed to survive years of harsh use and conditions.
So where am I? I used my D3100 for a couple years on automatic and once I started shooting manual I got the bug for a more capable camera. I moved up to the D7100 (which I still use) and added a full frame D750 to my lineup. I am very happy with my D750 and won’t be buying a new camera for some time.
Next article we will talk about lenses and how they are in some ways the more important investment than the camera body.
If you click on the above links to Amazon and make a purchase, I get a little cut so thanks! If this article has been useful, please share it on facebook!by Rich
Shutter Speed defines how long the camera’s “window” is open to capture the available light and therefore the image. The shorter the Shutter Speed, the more light is required (or the more a camera’s sensitivity to light matters) to get a proper exposure. Alternatively, a longer Shutter Speed has more time to gather light and can be over-exposed if there is too much light.
Examples of a shot requiring a fast shutter speed would be of a hummingbird’s wings mid-flight or a Formula 1 race car at top speed. In these cases, a very short Shutter Speed (into the 1000th of a second or more) is necessary to freeze the action.
An example of a longer Shutter Speed might be anywhere from a half-second to a multi-minute or longer exposure maybe in an evening venue or photographing the evening sky filled with stars.
So how can you figure out what SS is required for a given shot? You can just put your camera on Auto and then check to see what settings the camera picked, you can decide on a desired SS and select Shutter Priority (S for Nikon Tv for Canon) and let the camera pick the Aperture to get the proper exposure or you can go to my new favorite setting Manual and set SS, Aperture and ISO for yourself!
So what if you want a faster SS than you can achieve with your widest Aperture? You can bump up your ISO to make the sensor more sensitive to light. This is a good place to experiment. Depending on how new/good your camera is you may be able to bump ISO up above 1000 to get that faster SS you need for your shot.
On the other end of the spectrum, you may find yourself wanting to do a longer exposure to achieve a silky effect on flowing water or to give a surreal look to moving clouds during the day. In this case you may need to apply a neutral density filter that blocks some of the light. ND filters come in varying densities that can add multiple “stops” worth of light blocking to allow you to take longer exposure shots during the day.
I’ll write a future post on photographing star-trails, light trails and other long-exposure trickery. Next up: ISOby Rich
In this post we will discuss Aperture and its role in the Exposure Triangle. Aperture is the size of the hole that gathers light for your lens and the camera. The larger the hole, the more light can be gathered in a given amount of time. Just to be confusing, the larger the number, the smaller the hole. It makes more sense if you think of it as a fraction.
Another aspect of Aperture is in determining the Depth of Field (DOF) of the exposure.
You might want a shallow depth of field with a blurred background (called Bokeh) for a portrait of an individual where you want the focus of the picture to be on your subject, not the background.
Here is an example of a portrait shot with good bokeh of my son Griffin.
Here are a couple of examples.
All of these shots were taken at different Apertures from F/16 to F/1.8. So from these, we can learn that the smaller the Aperture number (which means the larger the “hole”) the shallower the Depth of Field. The blurry background you achieve with a shallow DOF is referred to as . Alternatively, the smaller the hole (larger Aperture number) the deeper the Depth of Field. The lens I used was a prime lens meaning it has only one focal distance (no zoom) so all of these were taken with an 85mm lens. (Full disclosure I have a DX frame camera, so the focal length is about 1.5 x 85mm, a topic for another post).
The above image was taken at an Aperture of F/16 (smaller hole) and has a fairly deep Depth of Field
The next image was taken at an aperture of F/4, a medium size hole with medium Depth of Field
The last image was taken at F/1.8 (large hole) and has a very shallow Depth of Field
So we discussed when you might want a shallow depth of field, when you have a single subject or subjects lined up at the same distance from the camera. You would want more depth of field if you were trying to shoot subjects that are not the same distance or a landscape shot. The important thing to remember is that all of these are guidelines, not rules. Feel free to deviate and see what your camera will do!
f/20 with some good depth of field.
Next we will look into Shutter Speed. If you find these posts interesting, please share them on Twitter or Facebook! Thanks!
Questions and comments welcome as always!
When you take a picture with a camera it is called an exposure. How an exposure looks depends on 3 settings on your camera. Aperture, Shutter Speed and the ISO. We will discuss each of these and what impact they can have on your photo.
Aperture is the size of hole in your lens that allows light into the camera. It is also commonly referred to as an F-stop since the Aperture is the letter F followed by a number. Just to be confusing, the smaller the number, the larger the hole, so F1.4 is a very large opening while F22 is a small opening. In general, the smaller the F-stop number (and therefore the larger the hole) the more light can enter the camera in a given time.
Shutter Speed is how long the hole (Aperture) is left open to collect light. This is usually listed as a fraction of a second or number of seconds. This can vary from a very fast shutter speed like 1/8000 of a second to leaving the shutter open for minutes at a time. The faster the shutter speed, the better you can capture or stop action. The slower the shutter speed, the more light you can collect, especially useful in low-light conditions or to capture the blur of motion.
ISO (International Standards Organization) is the acronym developed during the days of film camera where film was categorized by how “fast” it was which really means how sensitive it is to light. A “faster” film collected more light than a “slower” film. Film speeds generally varied from ISO 100 to ISO 800. Today with digital cameras the same ISO numbers apply, but you (or the camera) can choose them and change them between shots, unlike the film days where you had to use an entire roll before you could switch to another ISO. In general, you would use a lower ISO when you have plenty of light (or in some cases you are shooting a longer exposure) while higher ISO is better for low light conditions. One downside of a high ISO is that you can end up with a grainy look depending on your camera’s ability in low light.
So when you take a picture on Automatic, the camera decides what Aperture, Shutter Speed and ISO to use. If you switch your camera to Aperture Priority (A, not to be confused with AUTO), you can select the Aperture yourself and the camera will decide on the best of the other two. Same thing for Shutter priority (S or Tv on Canon) , you pick the shutter speed and the camera decides on the best for the other two. If you switch your camera to Manual (M on most cameras) you are in complete control of all three! SCARY!!
These are the basics of the Exposure Triangle, we will dive into more detail on each in later posts.
Below is an info-graphic which captures the pieces of the Exposure Triangle we have discussed below. The first block shows you what the Exposure window on your camera looks like, you adjust one or more of the three exposure elements to position the marker at zero take a balanced picture. The second graphic shows what the Aperture looks like at different settings. The third graphic shows the Shutter Speed and gives an idea how that works. The last graphic shows the ISO and how ISO sensitivity affects your exposure.
I’ve also included a link to my Pinterest page of Photography info-graphics. It is a wealth of helpful Photography Tips and Tricks. Check it out!
I’ve had a DSLR for about 4 years. I’ve gotten some nice pictures, but nothing really great. I knew I needed to do something different. This winter my wife and I visited our good friends who live in Key West. She is a professional photographer (see her work at www.deborahgrooms.com)and he might as well be himself when he’s not distilling some of the world’s best rum (http://papaspilar.com/). I picked both of their brains and toured the island with them learning about some of the settings on my Nikon D3100, which is my entry-level DSLR. Here’s a couple shots:
My plan is to do a series of blog posts discussion different aspects of photography. I will apologize upfront that I am still learning and am very much an amateur at this point. If you have specific questions or would like a post on a certain topic, tell me in the comments. Thanks for reading!